Global land and ocean surface temperatures in the first half of 2010 were the warmest January-June on record, the federal climate service reported Thursday.

January-June temperatures averaged 57.5 degrees Fahrenheit — 1.22 degrees F above the 20th Century average, according to the National Climatic Data Center. Its records go back to 1880.

That broke the previous record of 1.19 degrees F above average set in 1998.

In addition, last month was the warmest June on record at 61.1 degrees F — 1.22 degrees F above the 20th Century average.

2010 has also surpassed 1998 for the most "warmest months" in any calendar year, the center stated.

"Each of the 10 warmest average global temperatures recorded since 1880 have occurred in the last fifteen years," it added. "The warmest year-to-date on record, through June, was 1998, and 2010 is warmer so far."

The warmest year on record is 2005, but that record could fall as well.

The center also reported opposite ice developments on opposite sides of the globe:

Arctic sea ice covered an average of 4.2 million square miles during June — "10.6 percent below the 1979-2000 average extent and the lowest June extent since records began in 1979. This was also the 19th consecutive June with below-average Arctic sea ice extent."

"Antarctic sea ice extent in June was above average, 8.3 percent above the 1979-2000 average — resulting in the largest June extent on record."

The center, which calls itself "the largest active archive of weather data," gets monthly updates from national weather bureaus around the world.

Video: California endures heat wave

Transcript of: California endures heat wave

BRIAN WILLIAMS, anchor:It's been a hot summer across the country already, but this has been an especially long and hot day in parts of the
American West
.
Look
at some of the high temperatures today.
California
,
Nevada
,
Arizona
well over 100 degrees. And stress and people -- stress on people and the power grid as a result over several states.